RADAR/ADS-B outage and reporting.

[EdFred]

So a storm rolled through last night and the power went out at my place, and I got to thinking.
What happens if all the radar goes out for a large swath of airspace? Back when we were all on V's and J's separation becomes rather easy during a RADAR outage. Everyone is on a known, traceable, path, we report where we are, ETA for the next fix, and the controllers tell whoever to speed up/slow down/change altitude, to maintain separation. But now with "everyone" having GPS and being cleared direct across multiple sectors/centers the organized flow is now a random spiderweb of pathways.

So what happens if there's a widespread outage? I'm pretty sure the controllers aren't going to ask us to report LAT/LONG, ground speed, and a course heading and then they sit down with a giant sheet of paper and start making vector diagrams to see if 123AB is going to collide with 456CD.

What's the protocol if everything goes black?

 

[azure]

Whether it's widespread or not, a radar outage should have the same consequences. The radar site that would normally service the Adirondacks area was once out when I was flying from MI to VT. They gave me a choice: accept an airway reroute or climb to 11,000. I chose 11,000. I assume they had backup radar somewhere else that could see me that high.

Now if by "widespread" you mean all radar owned by a particular facility, then I assume they'd put everyone on airways and require position reporting. But I don't know for sure.

 

[flyingron]

ATC has to follow non-radar procedures if the radar is out.

This has happened to me...

ZDC: I'm going to have to put you on an airway...Seymour's radar is out. advise when ready to copy.


Got to go do the old PTATEN thing too

 

[EdFred]

OK, but I imagine it to be a big cluster to put everyone on an airway and not end up with separation/collision issues. I can see plane A fly perpendicular to the airway, while B heads to the nearest intersection/FIX, while C takes a 45 degree path to intercept...

This isn't a we know the next handoff is non-RADAR, I'm going to get you on an airway, but instant loss over a whole Z__ and underlying TRACONs I'm asking about.

 

[Velocity173]

It is a cluster when the radar goes out. Look at what happened in Chicago with a fire that took out their comms. When something major breaks and other facilities pick up the slack, it can be a pain.

With all the fusion type radars now, odds of everything going out would be slim. Single source TRACON radar, you have no choice but to either start non radar procedures, or turn the airspace over to center.

For non radar, you're gonna have everyone on airways and you'll seperate by either time or distance depending on aircraft equipment capability. Separation distance will also depend on factors such as speed or airway angles. All the separation will obviously be based on non radar position reports on compulsory fixes or ATC assigned fixes. Almost impossible to have all the standards of separation memorized. We used to have a cheat card in our wallets for the very few times the radar went down.

Once the aircraft arrive to their destination they'll have an IAP fix and will arrive stack in 1,000 ft increments. Aircraft will depart in timed approaches. I believe the standard is usually 2 minute intervals.

 

[MAKG1]

Something no one seems to know about -- ATC is aware of the physics of planned routes, between sectors and even between Centers. If you have a clearance and a filed TAS, Center can predict when you'll enter a TRACon's airspace and sequence you onto the approach, based on the last available information and cleared routes.

Google "Traffic Management Advisor" and "Final Approach Spacing Tool." Both have been deployed for some 15 years or so.